Login with facebook error: ERR_TOO_MANY_REDIRECTS – Facebook api

I am trying to login with facebook but i am getting too many redirect error. Please help me how to fix it.

I have tried Browser cookie clear does not work.

<?php
require 'facebook/facebook.php';
require 'config/fbconfig.php';
require 'config/functions.php';

$facebook = new Facebook(array(
            'appId' => APP_ID,
            'secret' => APP_SECRET,
            ));

$user = $facebook->getUser();

// I think i am not getting user. So i get 0 in user.
if ($user) {

  try {
    // Proceed knowing you have a logged in user who's authenticated.
    $user_profile = $facebook->api('/me');
  } catch (FacebookApiException $e) {
    error_log($e);
    $user = null;
  }

    if (!empty($user_profile )) {
        # User info ok? Let's print it (Here we will be adding the login and registering routines)
        $username = $user_profile['name'];
        $uid = $user_profile['id'];
        $email = $user_profile['email'];
        $user = new User();

                $img = file_get_contents('https://graph.facebook.com/'.$user_profile['id'].'/picture?type=large');
                $file = $_SESSION['SITE_IMG_PATH'].'userimage/'.$user_profile['id'].'.jpg';
                file_put_contents($file, $img);
                $userimage=$user_profile['id'].'.jpg';
        $userdata = $user->checkUser($uid, 'facebook', $username,$email,$twitter_otoken,$twitter_otoken_secret,$userimage);

        if(!empty($userdata)){
            session_start();
            $_SESSION['frontuser_info'] = $userdata;

            $Qparam=$fid.''.$sid.''.$tid;

            header("Location: ".$_SESSION['APP_PATH']."".$Qparam);

        }
    } else {
        # For testing purposes, if there was an error, let's kill the script
        die("There was an error.");
    }
} else {

    # There's no active session, let's generate one

    $login_url = $facebook->getLoginUrl(array( 'scope' => 'email'));

    # i think it is always coming here thats error.
    header("Location: " . $login_url);
}

?>

Please see code and help me to fix this redirection error i am always going in else part thats error.